Fortran overviewinput output syntax read

Type Declaration:- [Generalised Syntax] REAL :: list of names INTEGER :: list of names

Program Naming:- PROGRAM name IMPLICIT NONE Block of FORTRAN code goes here	• May contain only A to Z (or a to z), the digits 0 to 9, and the underscore character _ • Maximum of 32 characters!

[Generalised Syntax] *READ ,** list of names *PRINT ,** list of names [Examples] *READ , first, second, x1, y1, x2, y2 PRINT , “Your age now is ”, age* *PRINT , “Your age next birthday will be ”, age + 1**

MECH1004 COMPUTING / 2. Fortran Overview

In order to be able to run older Fortran programs using modern and more efficient compilers, implicit
declaration remains active unless “switched off” by the IMPLICIT NONE statement.

MECH1004 COMPUTING / 2. Fortran Overview 2.3 From Source Code to ““Executable

SALFORD FORTRAN DEVELOPMENT SOFTWARE

COMPILER		Binary File “Object Code”(unlinked)	.obj file
LINKER	link	Binary File “Executable Code” (fully linked)

Non--Executable Executable / / Executable PROGRAM age_next_year IMPLICIT NONE ! This program works out the user’s age ! after his/her next birthday

3. Handling Numbers

REAL :: a1, a2 INTEGER :: total ... ...	PROGRAM demo_2 IMPLICIT NONE ... REAL :: a1, total INTEGER :: a2 ... Within the assignment expression for total, a2 would effectively be converted to REAL before calculation.

MECH1004 COMPUTING / 3. Handling Numbers 3.1 How Numbers are Stored Storage of INTEGERS using 8 digits (in a hypothetical computer):- might represent +49 999 999 N.B. in a real computer the digits would be binary digits, so you would need lots more digits to represent these sorts of numbers.

MECH1004 COMPUTING / 3. Handling Numbers

� On the same typical 32-bit machine default REALs can range between about -1038and +1038, with 7 or 8 significant decimal digits. But note that they may vary slightly from theoretically“true” values due to rounding rounding or truncation truncation processes that occur within the CPU.

� Default REALs in Fortran normally use twice the amount of space as default INTEGERs.

Within the same level of priority, evaluation proceeds from left to right. a = b + c * d / e – f ** g / h + i * j + k

Other useful intrinsic functions for exercises 3:-FRACTION (X) MOD (A, P) INT (A) NINT (A) AINT (A) ANINT (A)

MECH1004 COMPUTING / 3. Handling Numbers 3.4 Intrinsic Functions Available
See list provided in hardcopy.

[Generalised Syntax]
function (name)
function (expression)

“angle” in degrees

MECH1004 COMPUTING / 3. Handling Numbers